Resilient, metallic sealing rings are well known in the art for sealing between a pair of coupled concentric, hollow annular bodies having high temperature and pressure fluid flowing therethrough. These sealing rings have numerous configurations, usually depending upon the cavity to be sealed. While these seals are effective in many situations, a need has long existed for a resilient metallic sealing ring capable of maintaining a tight seal between two cylindrical surfaces that expand at different rates, due to differences in their temperatures or in their coefficients of thermal expansion. The basic problem with providing such a seal is that the expansion of the cylindrical surfaces tends to compress the seal beyond its elastic range and thus the seal does not recover to a sealing configuration once the expansion cycle is completed. In other words, the cross sectional width of the sealing ring is permanently decreased, thereby causing leakage to commence almost as soon as the differentially expanded cylindrical surfaces begin to return to their original dimensions. This is usually caused by significant bending deflections in the seals.
Examples of U.S. patents disclosing prior art annular seals are: 2,774,618 to Alderson; 3,490,777 to Emmerson; 3,561,793 to Rode; 3,751,048 to Rode; 3,797,836 to Halling; 3,857,572 to Taylor et al; 3,869,132 to Taylor et al; 4,054,306 to Sadoff, Jr. et al; 4,121,843 to Halling; 4,218,067 to Halling; 4,281,841 to Kim et al; and 4,336,943 to Chaplin. U.K. Pat. No. 1,511,384 also discloses a prior art annular seal.